Splenic Artery Pseudoaneurysm Masquerading as a Pancreatic Cyst-A Diagnostic Challenge.

Splenic artery pseudoaneurysm is a rare entity. Clinical diagnosis is challenging because presentation is often varied. It can range from an incidental finding to hemodynamic collapse from sudden rupture and bleeding. The most common cause of this condition is pancreatitis. We report an unusual case of a young man not known to have pancreatitis who presented with hematemesis with normal esophagogastroduodenoscopy. Imaging modalities did not lead to a definitive diagnosis, and he underwent emergency laparotomy with surgical ligation of splenic artery pseudoaneurysm for hemodynamic instability, without a definitive preoperative diagnosis.

Five year experience in management of perforated peptic ulcer and validation of common mortality risk prediction models - are existing models sufficient? A retrospective cohort study.

BACKGROUND: Emergency surgery for perforated peptic ulcer (PPU) is associated with significant morbidity and mortality. Accurate and early risk stratification is important. The primary aim of this study is to validate the various existing MRPMs and secondary aim is to audit our experience of managing PPU. METHODS: 332 patients who underwent emergency surgery for PPU at a single intuition from January 2008 to December 2012 were studied. Clinical and operative details were collected. Four MRPMs: American Society of Anesthesiology (ASA) score, Boey's score, Mannheim peritonitis index (MPI) and Peptic ulcer perforation (PULP) score were validated. RESULTS: Median age was 54.7 years (range 17-109 years) with male predominance (82.5%). 61.7% presented within 24 h of onset of abdominal pain. Median length of stay was 7 days (range 2-137 days). Intra-abdominal collection, leakage, re-operation and 30-day mortality rates were 8.1%, 2.1%, 1.2% and 7.2% respectively. All the four MRPMs predicted intra-abdominal collection and mortality; however, only MPI predicted leak (p = 0.01) and re-operation (p = 0.02) rates. The area under curve for predicting mortality was 75%, 72%, 77.2% and 75% for ASA score, Boey's score, MPI and PULP score respectively. DISCUSSION AND CONCLUSION: Emergency surgery for PPU has low morbidity and mortality in our experience. MPI is the only scoring system which predicts all - intra-abdominal collection, leak, reoperation and mortality. All four MRPMs had a similar and fair accuracy to predict mortality, however due to geographic and demographic diversity and inherent weaknesses of exiting MRPMs, quest for development of an ideal model should continue.

Investigation of Volatile Mono-Aromatic Hydrocarbons and 1,3-Butadiene in an Urban Metropolis, India.

In urban areas, benzene, toluene, ethyl benzene and xylenes (BTEX) constitute up to 60% of nonmethane VOCs. The present work was conducted to determine the ambient volatile 1, 3-butadiene and mono-aromatic hydrocarbons in an urban metropolis of Nagpur, India. Continuous sampling was carried out at high density traffic junctions, major petrol filling stations along with some residential areas during March to May, 2011. The samples were collected in 10 litre tedlar bags during the peak hours and analyzed within 24 hours by VOC analyzer based on Gas Chromatography-Photo Ionization Detection technique. Appreciably high concentrations of Total BBTEX were observed at petrol filling stations (237.1 µg/m3) and traffic junctions (134.3 µg/m3). The levels of BBTEX observed around a major traffic junction were significant to commuter exposure. In view of the health impacts to commuter, nearby residents and occupational exposure, preventive measures like use of CNG, installation of vapor recovery system at petrol filling stations and use of mask by the workers were needed. The correlation analysis and concentration ratio study indicates the impacts of petrol pumps and vehicular traffic on the urban air quality at the residential sites. The levels of benzene were well within the National Ambient Air Quality Standards at all the residential locations.

A study of electro-mechanical and infrastructure instrumentation facilities in environmental laboratory.

Environmental laboratories carry out measurement and analysis of a number of physical, chemical and biological parameters. Each parameter requires some sort of instrument for its determination. Providing efficient instrumentation services to various departments of the Institute is an stupendous task. Instrumentation services in the form of installation, operation, repair and maintenanace of electro-mechanical equipment requires an in-depth experience and knowledge of the working, fabrication, design and repair of similar type of instruments so that the need of space, installation pre-requisites, budget constraints, availability of essential spares parts could be assessed. The paper discusses the operation of an environmental instrument repairs and maintenance, and audio-visual facilities. Suggestions for drafting of the proper specifications for procurement of laboratory equipments, such as ovens, furnaces, refrigerators, blowers, audio visual aids, and spares and accessories are given in this paper. The paper also gives the detailed information on various aspects that are needed for checking and testing of the equipment against specification before putting it in operational use. Development of a preventive maintenance program involving QC checks and keeping an inventory of essential spares required are also discussed in this paper. It is felt that such services are essential in providing smooth support to carry out research and development activities of the Institute.

Assessment of occupational exposure to VOCs at the Gantry gasoline Terminal.

The gasoline components dispersed in the workplace environment have direct impact on human health because of their carcinogenic and mutagenic potential. The volatile portion of these compounds generally consists of a mixture of monoaromatics such as benzene, toluene, ethylbenzene, xylenes and substituted benzene compounds. Investigation of levels of these chemicals at the petroleum liquid storage, and distribution facilities is of growing importance for assessing the occupational exposure of workers at these locations. A continuous monitoring was conducted at the Gantry Terminal of a refinery with portable samplers for determining 8-hr TWA at various locations involving petroleum liquid loading and distribution in road tank trucks, rail cars, and drums. After thermal desorption, the concentrations were determined in the laboratory with advanced Varian Model 2200GC/MS system. TVOCs level ranged between 0.10 to 1.97 mg/m3.The 8-hr TWA for benzene, toluene, and xylenes were low and within the limits for occupational exposure of gasoline components.

Decolorisation, biodegradation and detoxification of benzidine based azo dye.

The present study deals with the decolorisation, biodegradation and detoxification of Direct Black-38, a benzidine based azo dye, by a mixed microbial culture isolated from an aerobic bioreactor treating textile wastewater. The studies revealed a biotransformation of Direct Black-38 into benzidine and 4-aminobiphenyl followed by complete decolorisation and biodegradation of these toxic intermediates. From cytotoxicity studies, it was concluded that detoxification of the dye took place after degradation of the toxic intermediates by the culture.

Investigation of GC detectors performance and validation.

Detectors in gas chromatographs are used in many different ways. The functions varies with the requirement of sensing the chemicals at trace levels to measuring quantitatively the relative amounts of compounds in ppb to sub ppb levels. The requirement of minimum detectable sensitivity for GC detectors and its actual estimation during the analysis helps in assessing the performance of detectors and a stable response of the GC system. The paper reports the study carried out with a GC system equipped with detectors like Flame Ionization Detector(FID) and Electron Capture Detector(ECD). Both packed and capillary column have been used for estimating the minimum detectability of detectors. The FID sensitivity obtained is 1.14 coulombs/g C. The FID could minimum detect 2.65 x 10(-12) gram carbon per sec and ECD could minimum detect pesticides (Lindane) less than 1 femtogram. Such a procedure is useful for all those engaged in analysis with GC or are in the process of procuring good reliable GC system.

Operating environmental laboratories--an overview of analysis equipment procurement and management.

Management of equipment in an environmental laboratory requires planning involving assessment of the workload on a particular equipment, establishment of criteria and specification for the purchase of equipment, creation of infrastructure for installation and testing of the equipment, optimization of analysis conditions, development of preventive maintenance procedures and establishment of in-house repair facilities. The paper reports the results of such an analysis carried for operating environmental laboratories associated with R& D work, serving as an Govt. laboratory or attached to an Industry for analysing industrial emissions.

A comprehensive investigation of noise exposure in and around an integrated iron and steel works.

A comprehensive environmental noise exposure study was carried out in and around a major iron and steel works. The works was located in the central part of the city and was surrounded by residential, commercial, and sensitive receptors. Traffic activity near the plant was significant and added to the background noise level. Considering the variety of noise sources in the plant area and in the neighborhood, a practical approach to measure noise equivalent level in the plant and in the residential, commercial, industrial, and silence zone was adopted. A modular precision integrating sound level meter with statistical analyzer module, octave filter set, and calibrator were used during the measurements. The day and night level, Ldn, was determined. Worker exposure was assessed by determining the speech interference level (SIL), loudness level, and noise rating level at one of the major sources located in the power plant of the steel works. The results indicate that SIL was 94 dBA, loudness level was 112 phons, and the noise rating was in the range of 85-95. A traffic noise index also was determined near the works gates and was in the range of 68-96. The impact on the community is significant as observed from Ldn levels. Some mitigation measures for noise control are also discussed.

Inhibitory potential of neem (Azadirachta indica Juss) leaves on dengue virus type-2 replication.

In the present study we report in vitro and in vivo inhibitory potential of crude aqueous extract of neem leaves and pure neem compound (Azadirachtin) on the replication of Dengue virus type-2. In vitro antiviral activity of aqueous neem leaves extract assessed in C(6/36) (cloned cells of larvae of Aedes albopictus) cells employing virus inhibition assay showed inhibition in dose dependent manner. The aqueous extract of neem leaves at its maximum non-toxic concentration of 1.897 mg/ml completely inhibited 100-10,000 TCID(50) of virus as indicated by the absence of cytopathic effects. The in vivo protection studies with neem leaves extract at its maximum non-toxic concentrations 120-30 mg/ml resulted in inhibition of the virus replication as confirmed by the absence of Dengue related clinical symptoms in suckling mice and absence of virus specific 511 bp amplicon in RT-PCR. The pure neem i.e. Azadirachtin did not reveal any inhibition on Dengue virus type-2 replication in both in vitro and in vivo systems.

Development of low cost all glass recirculation systems for environmental applications.

Some simple glassware has been developed for recirculation of liquid medium. These glassware have wider applications and have been tested in experiments involving leaching, biodegradation, and desulfurization. The fabrication cost is minimum and can be developed in a small glassware workshop. Such a development has certain advantages as no separate mechanical devices are needed, the flow can be easily monitored due to transparency of the apparatus, acidic or alkaline medium can also be circulated. The paper discusses the development, design and fabrication of some specialized glass recirculation systems and its environmental applications.

Urban noise--a need for acoustic planning.

The noise status of growing urban centres of the country are very much required to develop acoustic design and planning guidelines for various land use classification. An attempt in this direction has been made by measuring noise equivalent levels for cities like Delhi, Jamshedpur, Dehradun and Nagpur. The choice of Ldn (Day-Night noise level) which is a better descriptor of noise quality provides an interesting status of noise in these urban centres. It has been observed that maximum percentage of areas in Delhi and Jamshedpur fall under moderately severe to very severe noisy conditions as compared to Dehradun and Nagpur on the noise rating scale. Ways and means are also considered for mitigation of noise.

Real time sound intensity measurements in an industrial complex.

The development of techniques and new tools for environmental acoustic measurements has opened up new ways and means to determine the source location, source ranking and energy flow path. The new tools posses versatile probes for different applications, better digital signal processing facilities and data presentation for sound pressure measurements--the quantity we hear, sound power measurements--the quantity emitted from a source, and the sound intensity measurements--the quantity of propogated sound power. The paper reports the results of real time sound intensity measurement carried out in an industrial complex with a portable sound intensity analyzer equipped with 1/3 octave filters and a dual microphone remote control probe for real time analysis. Extensive sound intensity measurement in the Power Plant, Ammonia Compressor House and Urea Compressor House have been carried out. The results are useful for sound power determination of various sources.

Escherichia coli responses to a single DNA adduct.

To study the mechanisms by which Escherichia coli modulates the genotoxic effects of DNA damage, a novel system has been developed which permits quantitative measurements of various E. coli pathways involved in mutagenesis and DNA repair. Events measured include fidelity and efficiency of translesion DNA synthesis, excision repair, and recombination repair. Our strategy involves heteroduplex plasmid DNA bearing a single site-specific DNA adduct and several mismatched regions. The plasmid replicates in a mismatch repair-deficient host with the mismatches serving as strand-specific markers. Analysis of progeny plasmid DNA for linkage of the strand-specific markers identifies the pathway from which the plasmid is derived. Using this approach, a single 1, N(6)-ethenodeoxyadenosine adduct was shown to be repaired inefficiently by excision repair, to inhibit DNA synthesis by approximately 80 to 90%, and to direct the incorporation of correct dTMP opposite this adduct. This approach is especially useful in analyzing the damage avoidance-tolerance mechanisms. Our results also show that (i) progeny derived from the damage avoidance-tolerance pathway(s) accounts for more than 15% of all progeny; (ii) this pathway(s) requires functional recA, recF, recO, and recR genes, suggesting the mechanism to be daughter strand gap repair; (iii) the ruvABC genes or the recG gene is also required; and (iv) the RecG pathway appears to be more active than the RuvABC pathway. Based on these results, the mechanism of the damage avoidance-tolerance pathway is discussed.

Mutagenesis induced by a single 1,N6-ethenodeoxyadenosine adduct in human cells.

To study the genotoxic properties of 1,N6-ethenodeoxyadenosine (epsilondA) in human cells, a novel site-specific mutagenesis approach was developed, in which a single DNA adduct was uniquely placed in either strand of a shuttle plasmid vector. The analysis of progeny plasmid derived from the modified strand shows that epsilondA, when incorporated into the position of the second A of 5'-CAA (codon 61 of the ras gene), is mutagenic in human cells, inducing A-->T, A-->G, and A-->C mutations. The efficient induction of A-->T transversions in experiments using modified double- and singlestranded DNA substrates supports the hypothesis that A:T-->T:A transversions in human and animal tumors induced by vinyl compounds reflect misinsertion of dAMP opposite this adduct. Mutagenic events were similar when the adduct was incorporated into either the leading or the lagging strand. EpsilondA was more mutagenic than 8-oxodeoxyguanosine, which induced targeted G-->T transversions in HeLa cells. In Escherichia coli, epsilondA did not significantly miscode (<0.27%) even in the presence of induced SOS functions.

Cellular response to exocyclic DNA adducts.

The mutagenic potential of three exocyclic DNA adducts was studied in Escherichia coli and simian kidney cells by incorporating them into single-stranded DNA. Differences in the mutagenic potency of the adducts were observed between hosts: 1,N6-ethenodeoxyadenosine and 3,N4-ethenodeoxycytidine were more mutagenic in simian cells, whereas 1,N2-(1,3-propan-1,3-diyl)-2'-deoxyguanosine was more mutagenic in E. coli. To investigate the cellular response to DNA adducts, a double-stranded DNA vector system was developed. Use of this system showed that 1,N6-ethenodeoxyadenosine blocks DNA synthesis strongly, and DNA synthesis past this adduct was highly accurate in E. coli. The blockage of DNA synthesis was overcome in an error-free manner by the recombination repair mechanism (daughter-strand gap repair).

Comparison of two colorimetric assays to determine viral infectivity in micro culture virus titration.

Efficacy of two colorimetric assays, viz. MTT (3-4,5-dimethylthiazol-2-(yl-2,5-diphenyl tetrazolium bromide) and neutral red (NR) assays, performed by integrating them to micro culture virus titration (MCVT), was compared with the conventional MCVT method in terms of percentages of infectivity and 50% infectivity end points by employing Polio virus type-3 and Dengue virus type 4 as the candidate viruses. The results suggested that MTT assay has an edge over NR assay as well as conventional MCVT method. For the first time, NR assay has been successfully employed for the determination of virus infectivity titre.

Inhibition of DNA cytosine methyltransferase by chemopreventive selenium compounds, determined by an improved assay for DNA cytosine methyltransferase and DNA cytosine methylation.

The organoselenium compounds benzyl selenocyanate (BSC) and 1,4-phenylenebis(methylene)selenocyanate (p-XSC), as well as sodium selenite, are effective chemopreventive agents for various chemically induced tumors in animal models at both the initiation and postinitiation stages. The mechanisms involved at the postinitiation stage are not clear. Because several lines of evidence indicate that inhibition of excess DNA (cytosine-5)-methyltransferase (Mtase) may be a sufficient factor for the suppression or reversion of carcinogenesis, we examined the effects of sodium selenite, BSC, p-XSC and benzyl thiocyanate (BTC), the sulfur analog of BSC, on Mtase activity in nuclear extracts of human colon carcinomas, and of p-XSC on the Mtase activity of HCT116 human colon carcinoma cells in culture. For this purpose, we developed an improved Mtase assay, in which the incorporation of the methyl-[3H] group from S-adenosyl[methyl-3H]methionine into deoxycytidine of poly(dI-dC)-poly(dI-dC), is specifically determined by HPLC with radioflow detection after enzymatic hydrolysis, enhancing specificity and reliability. In a variation, using SssI methyltransferase and labeled S-adenosylmethionine, the overall methylation status of DNA in various tissues can also be compared. Selenite, BSC and p-XSC inhibited Mtase extracted from a human colon carcinoma with IC50s of 3.8, 8.1 and 5.2 microM, respectively; BTC had no effect. p-XSC also inhibited the Mtase activity and growth of human colon carcinoma HCT116 cells, with an IC50 of approximately 20 microM. The improved Mtase assay should prove to be a reliable method for screening potential Mtase inhibitors, especially using cells in culture. We suggest that inhibition of Mtase may be a major mechanism of chemoprevention by selenium compounds at the postinitiation stage of carcinogenesis.